The present invention relates to a cutting head and method for cutting wood chips, particularly for cutting and finishing the surface of the wood in one operation.
Wood that is first obtained in the form of logs generally must be processed to provide finished lumber for use in construction. Often in this processing, a log is cut first to desired dimensions and cut again for surface finishing. Lumber having a higher finish requirement is referred to as being of a higher "grade."
Cutting apparatus typically employ drum-style surfacing "heads," which include a rotating cylinder on which is mounted a plurality of knives for cutting the surface of the wood, which may be lumber or logs. The wood is fed while supported on a horizontal support surface along a generally horizontal path that results in the grazing of the surface of the wood by the knives. Wood chips are thereby removed from the surface of the wood to a predetermined depth. For higher grade lumber, it is typical that such apparatus is not able to provide a satisfactory surface finish. One problem is that the knives cutting the wood cause the wood to vibrate and bounce, thereby deflecting it episodically in a direction perpendicular to the axis of rotation of the head. This results in an uneven or irregular surface which often must be processed further to obtain desired surface planarity, which adds cost and reduces yield.
Accordingly, there is a need for a wood surfacing head and method that provides for cutting the wood while at the same time providing improved finishing of the surface of the wood, thereby providing a lumber grade recovery.